This invention relates to a door closer or a device for controlling the opening or closing movement of a door and, particularly, to a door closer with a simplified construction and a minimized size.
One prior art door closer comprises, for example, a casing forming an outer body of the door closer, a buffer device or drive means disposed in the casing and including a piston-piston rod assembly slidably fitted in a cylinder containing hydraulic oil therein and a check valve or the like disposed in the piston for generating hydraulic resisting force when the piston moves in one direction, a generally U-shaped actuating plate with rack teeth formed therein and secured to the extreme end of the piston rod which projects outside of the buffer device, the actuating plate being bent at the mid-portion thereof such that a portion of the plate extends in a direction away from the buffer device, a pinion meshingly engaging with the rack teeth and rotatable in association with the opening-closing movement of the door, and a metal spring interposed between the actuating plate and the casing.
The door closer having the construction described above has a substantial length in the direction of the axis of the door closer. Thus, space for mounting the door closer is very large and the construction of the door closer is complicated.